A number of electronic circuits utilize flip-flops that have a state that can be set or changed depending upon the state of one or more inputs and optionally one or more outputs. A flip-flop can be utilized as a data storage element, a counter, a timing element, and/or the like.
Referring to FIG. 1, an exemplary data flip-flop according to the conventional art is shown. The exemplary data flip-flop includes a first input for receiving an input data signal d, a second input for receiving a clock signal clk and an output q. The state of the output q changes in response to a change of state of the input data signal d when the clock signal clk changes state.
Referring now to FIG. 2A, a first exemplary circuit of a data flip-flop according to the conventional art is shown. The exemplary data flip-flop circuit includes a master latch sub-circuit 201, a slave latch sub-circuit 220, and optionally an output isolation sub-circuit 230. The output q changes state in response to a change in state of the input data signal d when the clock signal clk changes state.
Referring now to FIG. 2B, a second exemplary circuit of a data flip-flop according to the conventional art is shown. The exemplary data flip-flop circuit includes a master storage element sense amplifier sub-circuit 250, a slave latch sub-circuit 260, and optionally an output isolation sub-circuit 270. Again, the output q changes state in response to a change in state of the input data signal d when the clock signal clk changes state.
In a number of electronic circuits, the flip-flops consume a substantially portion of the power used by the electronic device. For example, a processor may include logic circuits, flip-flops, interface control group circuits, clock trees, random access memory and the like. FIG. 3 illustrates the dynamic energy consumed by the logic circuits, flip-flops, interface control group circuits, clock trees, and random access memory of an exemplary processor, such a central processing unit (CPU), graphics processing unit (GPU), digital signal processor (CPU) or the like. As illustrated, the flip-flop circuits may consume approximately one quarter of the power consumed during switching in the processor. Accordingly, to reduce power consumption in electronic devices there is a continuing need for improved flip-flops circuits.